The more I think about it, the more I have my reservations about hiding the top 100. Especially compared to the other ideas here, I really don't think that would do much to encourage more kills vs just annoying people...
I really like the idea of giving 1 extra Ruby pot for all players who reach a certain threshold but I wonder if 25k is achievable for lower-level players with limited stamina banks. I know I can reach it if my stamina is close to full at the start of the event and I use a high-level Conserve and get 2 good hunts in but it's still quite a challenge. In terms of fairness, I wonder if 20k kills would make more sense.
I am completely against basing the required kills around the player's stamina. While it makes sense to get a player with 10k stamina to get 20k kills, it is ridiculous to ask a player with 50k stamina to get 100k kills.
If HCS agrees to a tiered system for giving out extra Ruby chests, I don't think any of the proposed ones make much sense. There would definitely have to be a sliding scale such as 20k, 50k, 100k
This scale would give the top 3 contributors who each made over 100k kills 3 extra chests in addition to what they get for the top 100. Also, if HCS decides to implement such a scale, I think the bonus for top 100 should be dropped to just 1 additional chest or removed completely. Even if the bonus chests are removed from top 100, players will still battle for the top 100 medal and if they can reach 100k kills, 3 extra chests.